Ultracold gas mimics ultrahot plasma

Feb 15, 2009

Several years after Duke University researchers announced spectacular behavior of a low density ultracold gas cloud, researchers at Brookhaven National Laboratory have observed strikingly similar properties in a very hot and dense plasma "fluid" created to simulate conditions when the universe was about one millionths of a second old.

The plasma was formed at a colossal 2 million degrees Kelvin temperatures within Brookhaven's Relativistic Heavy Ion Collider (RHIC). The gas cloud was cooled to only .1 millionths of a degree Kelvin temperatures using a laser light "trap" and magnetic field at Duke. But both drastically different systems expanded something like exploding cigars. And their constituent matter also showed signs of flowing almost free of any viscosity -- a "nearly perfect" fluid, said Duke physics professor John Thomas.

"There's about 19 orders of magnitude difference in temperature and about 25 orders of magnitude difference in density, but the commonality of both is almost zero viscosity flow," said Thomas.

Thomas will report on his laboratory's experiments with "fermion" gases and their possible relevance to RHIC's "quark-gluon plasma" research as well as to string theory during a Sunday, Feb. 15 symposium organized by Brookhaven during the American Association of Science's 2009 Annual meeting, to be held in Chicago.

In a November, 2002 report in the research journal Science, Thomas and co-researchers described what happened after they confined a cloud of lithium-6 atoms and cooled them to 100 billionths of a degree above absolute zero. When the ultracooled, cigar-shaped cloud was then released from the trap, it expanded "anisotropically," meaning "fastest along the direction that was initially narrow," he recalled.

Lithium atoms are of the fermion class, meaning that that their spin-states normally make them keep more of a distance from each other than their chummier counterpart class of atoms -- the bosons. But under the extreme conditions of his experiments, even fermions find ways to collide to form what are called "strong interactions," he said.

Brookhaven's RHIC is designed to smash gold atoms together near the speed of light. Its goal is to create energies colossal enough to break apart their nuclei into an ultrahot gas of the most fundamental particles, "naked" quarks and gluons. Theoreticians believe such a "quark-gluon plasma" has not existed since a split-second after the Big Bang.

As the results of those experiments began to surface in April, 2005, RHIC experimenters found that "the cigar shaped plasma looked very much like the cigar- shaped cloud in our trap," Thomas said. That cloud also expanded anisotropically in keeping with what theorists in the field had predicted. Researchers also found that this plasma behaved as an almost-perfect fluid. Meanwhile, further work by Thomas's group has documented almost viscosity-free fluid states in its cold fermion gases.

Thomas noted that quarks themselves are also fermions. "So there's quite a broad overlap, and a genuine common interest in these two patterns. We don't have exactly the same system as at RHIC. But in a broad sense there are similarities that could be exploited to get some insight."

Meanwhile, researchers involved in string theory have also approached Thomas about similarities between his fermion findings and the predicted behavior of what those theorists call "strongly interacting quantum fields," he said. "It's not clear, though, that the prediction has any relevance to Fermi atoms colliding in a trap. However, the closeness of the initial cold gas measurements to the predictions is striking."

Elements of string theory aim at bridging the gap between quantum mechanics and general relativity by proposing that the true fundamental particles are actually ultra-tiny strings vibrating in multiple dimensions.

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User comments : 13

I don't pretend to understand the math or even the concepts behind much that I read about physics. That said, it appears that there are many fundamental things that even the experts do not fully understand.

As they continue to probe the conditions that they believe existed at the beginning of the universe, it seems to me that there is some risk of re-creating the event itself, with disastrous results to the universe we know.

A common reply is that they are creating these conditions with extremely small energies compared to the original event, and therefore actually creating a "big bang" is impossible.

If hovever, there are extra dimensions, as some experts suspect, without knowing exactly what exists within them, isn't it at least possible that creating conditions that could open them up release the energy necessary to effectively "re-boot" our universe?

Of course these experiments are probably being, or will be carried out on countless other planets, so we might might as well proceed anyway.

I don't pretend to understand the math or even the concepts behind much that I read about physics. That said, it appears that there are many fundamental things that even the experts do not fully understand.

As they continue to probe the conditions that they believe existed at the beginning of the universe, it seems to me that there is some risk of re-creating the event itself, with disastrous results to the universe we know.

A common reply is that they are creating these conditions with extremely small energies compared to the original event, and therefore actually creating a "big bang" is impossible.

If however, there are extra dimensions, as some experts suspect, without knowing exactly what exists within them, isn't it at least possible that creating conditions that could open them up release the energy necessary to effectively "re-boot" our universe?

Of course these experiments are probably being, or will be carried out on countless other planets, so we might might as well proceed anyway. Just something to think about.

From AWT perspective such finding is trivial, because every sufficiently hot&dense particle environment behaves like boson condensate from dual perspective. From insintric perspective it appears like cold and calm empty environment, simmilar to our vacuum. For example the surface of molten iron in blast furnace is quiet and calm liquid, the interior of Sun is probably quiet and transparent environment, and so on. AWT considers, our vacuum is formed by interior of giant dense star simmilar to black hole, which we are living in. Or at least it appears so.

Theoreticians believe such a "quark-gluon plasma" has not existed since a split-second after the Big Bang

Energy spreads very slowly inside of dense environment, the energy should spread by superluminal speed under such circumstances. If yes, contemporary physics has nothing to say about it. This "split-second" could be a quite long time interval from insintric perspective. How fast quasars explode into gallaxies?

Could it be possible that the particles of a laserbeam absorb the energy
radiating from the expanding qvarks with them?
This way energy radiating from the separate atomcores can not reach the
expanding atomcores nextby?

After that expanding qvarks of the separately expanding atomcores overlapp.

An energyconcentration that has composed of very dense energy has born and its hot / dense energy is able to keep itself hot / dense.
This way the energy of Bosen-Einstein condensate does not radiate nearly at all its energy away from itself!

(Maybe later The expanding qvarks have locked themselves to expand side by side?)

In the area between the expanding qvarks the moving photon meets so much dense energy that its movement slows down significantly.

For example the speed of a runner slows down involuntarily when the runner meets a traffic jam, but as soon as the runner meets a less dense space that does not transform, he can accelerate his speed. To accelerate his speed the runner must transform his body energyto a less dense energy! In other words the runner must make the substance that he consists of to transform faster than usually in a certain area to a less dense energy.

If the energy f a photon passing through the Bosen-Einstein condensate does not transform it is based on the fact that the particules are able to
recycle the energy they meet! Also the cores of expanding atoms are able to recycle the energy coming towards the core!

Did you know that everything that exists, it is one and the same thing which we canname energy.

This energy is not the matter, instead it is what exists inside of the atomic
nucleus of the matter and its density changes all the time to less density.

When there is no energy coming from outside, then it gets cold because the energy emission does not get from the atomic nucleus more of this energy to burst.For this reason, throughout expanding atomic nucleus do not push themselves away from each other so powerfully as earlier, at which point that into the atomic nucleus comes more of this energy in particles.

At the end, the so called quarks existing in different atomic nucleus interlace and form a quark unit.
Also, the energy existing inside the quarks changes all the time to less dense energy,moreover quarks burst out energy waves.

In the center of a quark unit big enough arises a sufficient pressure, whereupon quarks get to burst a lot of
energy towards each other. Therefore this quark unit starts to emit abondant energy from itself.
This way from the absolute zero we jump straight to high temperatures.

Let's talk about temperature in the absence of atom's oscillations, but rather how much energy one piece emits.
Also there is a meaning about the density of the emission: How the particles are and how close they are to one another.

At the same time an energy that is transforming to a less dense energy, pushes itself towards an area where exists less energy. This happens because the energy transforming to less dense doesn´t have te room to stay in a equally small area that doesn´t change.

Also the energy in the qvarks transforms all the time into a less dense energy.

From outside there doesn´t come almost at all energy towards the atomcores when reaching the absolute zero point. To atomcores in which the energy transforms all the time into a less dense energy. This way the expanding
atomcores do not expload their energy towards each other and they don´t push themselves away from each other so powerfully.

Eventually the qvarks of the separate atomcores interlock with each other. A big consentration of the qvarks has developed. Also in the middle of the centre a pressure has been developed. This pressure is based on a fact that
the qvarks radiate their energy towards each other. With this energy they push themselves away from each other according to the same relation as they expand.

An adequate pressure is developed in the middle of the big expanding consentration of the qvarks and this pressure makes the qvarks to explode a lot of their energy towards each other.

This is why a lot of energy begins to burst / radiate from the qvark consentration.

This is how extremely cold turns in a moment into extremely hot.

The heath is not a atomcores. The vibration of the atoms is consequence of outward coming energy that reaches the atomcores.

The so called "Caloric" is not a chemical element.

"Caloric" is the one and the same thing that exists in all atomcores. It can be called energy. Or with any other name.
Energy transforms all the time to a less dense energy in a space that does not change.

Also the movement of all the atoms of the world happens towards cold in other words towards a space where is less energy!
The expanding atoms push themselves towards a less dense area in space.

The energy of the planets push themself away from the sun in a curved orbit. There is more and denser energy than outside the sun.

The stars push themselves in a curved orbit away from the centre of the galaxy where is more and denser energy than in the outside of the galaxy.

The energy of the visible universe pushes itself away from the area that exists really far outside the visible universe.In that area there exists more and denser energy than in the visible universe. Outside that area energy is less denser.

The energy of the visible universe pushes itself towards the cold. In other words towards a less dense area in a space that does not change.